This invention relates to bags for making packages for different kinds of products such as potato chips, candies, cereal foods, salt, sugar and detergents.
As a trend in the modern world, more people are eating light snacks. As a result, enormous amounts of snack foods such as potato chips are being sold and consumed daily. When such snack foods are purchased by the consumer, they are usually packaged in laminated package bags, or package bags of different kinds such as the so-called pillow type, quadrangularly sealed type or standing paunch type. When the products thus differently packaged are transported by a wholesaler to retail stores, the shipments are usually made in corrugated fibreboard boxes, each box filled either mechanically or manually with a specified number of filled packaging containers. Because prior art types of packaging containers invariably include so-called dead spaces, these boxes become unnecessarily bulky. Since this inevitably affects the cost of transportation, there have been attempts to reduce the dead space as much as possible. Containers in the shape of a rectangular parallelopiped may be considered advantageous because they can be tightly packed inside a box and do not rattle too much when being transported but they tend to make their contents to appear too small. Other disadvantages of this type include that only a limited amount of articles can be packaged inside and that the packaged products are likely to be damaged.
In view of the above, Japanese Utility Model No. 2593457, Japanese Patent No. 7-293012 and U.S. Pat. No. 5,570,569 (issued Nov. 5, 1996 to Masuda) disclosed a packaging container as generally shown at 101 in FIG. 11, characterized as being made of a soft packaging material in the shape of a generally rectangular column (with a front wall 102, a back wall 103 and side walls 104) as well as a planar bottom and a uniformly sloped upper lid 106. These containers have been popular in the market because they can be packed efficiently inside a fiberboard box or the like, as shown in FIG. 12, and the dead space between the containers can be reduced as closely to zero as possible.
The package container 1 shown above is formed from a single sheet of soft packaging material by folding it forward and backward. After the sloped lid 106 is formed, the back wall 103 is made taller than the highest part of the sloped lid 106, protruding further above. This portion has no practical function and used to be cut off, and this amounted to a waste of material.